JP7157324B2 - FIBER, LIGHT EMITTING DEVICE USING THE SAME, AND MANUFACTURING METHOD THEREOF - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fiber, a light emitting device using the same, and a method for manufacturing the same.

Conventional light-emitting devices are manufactured by forming a nitride semiconductor layered structure on a planar growth substrate, cutting it into chips, and die-bonding them to a ceramic substrate or the like. are connected to each other and assembled into an LED device. In conventional flip-chip LEDs, the anode and cathode bump electrodes on one side of the LED chip are electrically connected to a ceramic substrate or the like using a brazing agent.

In such a conventional light-emitting device, since a semiconductor layer is grown on a circular growth substrate of several inches, there is a problem that management of the plate-shaped growth substrate is troublesome. In order to solve this problem, it has been proposed to use a fibrous substrate and grow a semiconductor on this fiber substrate (for example, Patent Documents 1 to 3).

However, in order to grow a semiconductor on a fiber substrate, it is necessary to heat the substrate, and it is not easy to heat the fiber. Furthermore, ensuring the heat dissipation of the manufactured light emitting device has also been a problem. In spite of this fact, the above-mentioned patent document does not show a specific solution method, and has poor practicality.

JP 2006-154589 A Japanese Unexamined Patent Application Publication No. 2015-2346 JP 2015-38853 A

One of the objects of the present invention is to provide a practical light-emitting device that uses an elongated fiber as a substrate instead of a plate-like substrate.

A light-emitting device according to an aspect of the present invention includes a fiber made of sapphire or spinel, and a semiconductor light-emitting structure formed on the outer peripheral surface of the fiber, wherein the fiber is made of sapphire or spinel. A metal core extending along the extension direction of the fiber can be provided inside.

With the above configuration, since the metal core is provided inside the fiber, heating during manufacturing is facilitated using the core. Also, stable operation is possible by using a metal core for heat dissipation of the obtained light-emitting element.

1 is a schematic perspective view showing a light emitting device according to Embodiment 1. FIG. 2A is a vertical sectional view of the light emitting device according to Embodiment 1, and FIG. 2B is a horizontal sectional view. 2B is an enlarged cross-sectional view of the semiconductor light emitting structure of FIG. 2A; FIG. 1 is a schematic perspective view showing an example of a fiber; FIG. 1 is a side view showing a light bulb using a light emitting element as a filament; FIG. 6A is a cross-sectional view of the fiber of the light-emitting element according to Embodiment 1, FIG. 6B is a cross-sectional view of the fiber of the light-emitting element according to Embodiment 2, FIG. 6C is a cross-sectional view of the fiber of the light-emitting element according to Embodiment 3, and FIG. 6D. 12] is a cross-sectional view of a fiber of a light emitting device according to Embodiment 4. [FIG. It is a schematic diagram which shows the light emitting element which concerns on a modification. 8A is a vertical sectional view of a light emitting device according to Embodiment 5, and FIG. 8B is a horizontal sectional view. 9A is a vertical sectional view of a light emitting device according to Embodiment 6, and FIG. 9B is a horizontal sectional view. 10A is a vertical sectional view of a light emitting device according to Embodiment 7, and FIG. 10B is a horizontal sectional view. 11A is a vertical sectional view of a light emitting device according to Embodiment 8, and FIG. 11B is a horizontal sectional view. 12A is a vertical sectional view of a light emitting device according to Embodiment 9, and FIG. 12B is a horizontal sectional view. FIG. 13A is a vertical cross-sectional view showing one step of the manufacturing process of the light emitting device, and FIG. 13B is a cross-sectional view. It is a side view which shows one process of the manufacturing process of a light emitting element. FIG. 15A is a vertical cross-sectional view showing one step of the manufacturing process of the light emitting device, and FIG. 15B is a cross-sectional view. FIG. 16A is a vertical cross-sectional view showing one step of the manufacturing process of the light emitting device, and FIG. 16B is a cross-sectional view.

According to the light-emitting device of one embodiment of the present invention, tungsten or iridium can be suitably used as the core.

Further, according to a light emitting device according to another embodiment, the semiconductor light emitting structure can be a nitride semiconductor laminated structure.

According to the light emitting device according to still another embodiment, <0001> of the sapphire or <111> of the spinel can be aligned with the cross-sectional direction intersecting the extension direction of the fiber.

Furthermore, according to the light emitting device according to another embodiment, the cross section of the fiber can be formed in a circular shape.

Furthermore, according to a light emitting device according to another embodiment, a plurality of the semiconductor light emitting structures can be spaced apart along the extending direction of the fiber.

Furthermore, according to a light emitting device according to another embodiment, the separated semiconductor light emitting structures each have positive and negative electrode portions, and the respective semiconductor light emitting structures can be connected in series via the respective electrode portions.

Furthermore, according to a light-emitting element according to another embodiment, the core can be connected to a heat dissipation member.

Furthermore, according to a method for manufacturing a light-emitting device according to another embodiment, the steps of preparing a fiber made of sapphire or spinel and including a metallic core body extended in a fibrous shape; growing a semiconductor light-emitting structure on the outer periphery of the fiber under heating.

Furthermore, according to the method of manufacturing a light-emitting device according to another embodiment, <0001> of the sapphire or <111> of the spinel can be aligned with the cross-sectional direction intersecting the extending direction of the fiber.

Furthermore, according to a method for manufacturing a light-emitting device according to another embodiment, the step of preparing the fiber may include the step of growing the sapphire or spinel by a μ-PD method.

Furthermore, according to a method for manufacturing a light emitting device according to another embodiment, the step of preparing the fiber may include the step of growing the sapphire or spinel by the LHPD method.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments and examples according to the present invention will be described based on the drawings. However, the embodiments and examples shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following. Also, the sizes and positional relationships of members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same names and symbols indicate the same or homogeneous members, and detailed description thereof will be omitted as appropriate. Also, parts with the same reference numerals appearing in a plurality of drawings indicate the same or equivalent parts or members. Furthermore, each element constituting the embodiments and examples according to the present invention may be configured by forming a plurality of elements with the same member, and one member may be used as a plurality of elements, or conversely, one member function can be shared by a plurality of members. Also, the contents described in some of the examples and embodiments can also be used in other examples and embodiments. In addition, the following description uses terms indicating specific directions and positions (e.g., "top", "bottom", "right", "left", and other terms that include those terms) as necessary. However, the use of these terms is for the purpose of facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meanings of these terms. In this specification, the term "comprising" is used in the sense of including both those provided as separate members and those configured as an integral member.
[Embodiment 1]

A light emitting device 100 according to Embodiment 1 of the present invention is shown in FIGS. 1 to 3. FIG. In these figures, FIG. 1 is a perspective view of the light emitting device 100 according to Embodiment 1, FIG. 2A is a vertical cross-sectional view of the light emitting device 100 according to Embodiment 1, FIG. 2B is a cross-sectional view, and FIG. An enlarged cross-sectional view showing light emitting structure 20 is shown, respectively. A light-emitting device 100 shown in these figures comprises a fiber 10 and a semiconductor light-emitting structure 20 formed on its outer peripheral surface. Here, as shown in FIG. 2A, a plurality of semiconductor light emitting structures 20 are arranged along the length direction of the fiber 10 and adjacent semiconductor light emitting structures 20 are insulated. Each semiconductor light emitting structure 20 has a stacked structure of semiconductor layers grown on the fiber 10, as shown in the enlarged cross-sectional view of FIG. As described above, the light emitting device 100 uses the fiber 10 as a growth substrate and forms the semiconductor light emitting structure 20 on the outer peripheral surface of the fiber 10 .

FIG. 4 shows an example of a single-crystal fiber substrate. This fiber 10 has a metal core body 12 extending along the extension direction of the fiber 10 inside the fiber 10 . By using this fiber 10 as a substrate and growing a semiconductor light emitting structure 20 around it, the light emitting device 100 of FIG. 1 can be obtained. Thereby, a light-emitting element such as an LED can be made into a filament-like string shape. By making the light emitting element filamentary in this way, it becomes possible to wind the light emitting element, and the maintenance becomes easier than when the semiconductor light emitting structure 20 is grown on a circular substrate. Further, with this configuration, it is possible to omit a mounting board made of ceramic or the like, which is conventionally required.

Furthermore, since such a string-shaped light-emitting element 100 can be formed in a filament shape with a very small diameter, for example, when it is used as a backlight source for a liquid crystal display, it can be edge-lit by surrounding the light guide plate in a string-like manner. Available with backlighting method.

Alternatively, as shown in FIG. 5, by using a string-shaped light-emitting element 100 as the filament of the light bulb LB, it is possible to emit light around the filament-shaped light-emitting element so that it can be suitably used as a bulb-type illumination.
(fiber 10)

As the base material of the fiber 10, sapphire can be suitably used as a material having excellent translucency and thermal conductivity. In particular, single crystal sapphire is preferable because it facilitates the growth of the semiconductor light emitting structure 20 on the upper surface. Also, spinel may be used instead of sapphire.

The cross-sectional dimension of the fiber 10 can be of any size, but from the standpoint of fiber availability, ease of manufacture, etc., it is preferably 50 to 500 μmφ. Also, the length of the fiber 10 can be appropriately selected according to the application, and can be designed, for example, from several centimeters to several kilometers.

The cross-sectional profile of the fiber 10 is preferably circular. However, the present invention does not limit the outer shape of the cross-section of the fiber to a circular shape, and may be of various shapes as shown in FIGS. 6A to 6C. 6A is a cross-sectional view of the fiber 10 of the light-emitting device 100 according to Embodiment 1, FIG. 6B is a cross-sectional view of the fiber 10B of the light-emitting device according to Embodiment 2, and FIG. 6C is a cross-sectional view of the light-emitting device according to Embodiment 3. A cross-sectional view of the fiber 10C and FIG. 6D show a cross-sectional view of the fiber 10D of the light emitting device according to Embodiment 4, respectively. First, FIG. 6A is a cross-sectional view of the fiber 10 of the light emitting device 100 according to Embodiment 1, which has a circular shape. Moreover, the fiber 10 is not limited to a circular shape, and may be elliptical. In Embodiment 2, the outer shape of the cross section of the fiber substrate is elliptical. As a result, by aligning the axis (for example, <0001> of sapphire) capable of efficiently growing the semiconductor light-emitting structure 20 in a direction that overlaps with the minor axis of the elliptical shape viewed as a true ellipse, a large number of regions can be efficiently grown. can be secured. Further, the outer shape of the cross section is not limited to a circular shape or an elliptical shape, and may be a rectangular shape. For example, in Embodiment 3 shown in FIG. 6C, the fiber 10 has a square cross-sectional shape. In Embodiment 4 shown in FIG. 6D, the fiber 10 has a rectangular cross-sectional shape. This provides the advantage of facilitating positioning when arranging. For example, in the above-described example in which the string-shaped light emitting elements are arranged around the light guide plate, optical coupling can be easily established by bringing a flat surface having a rectangular shape in cross section into contact with the periphery of the light guide plate.
(Core body 12)

A metal core 12 is arranged inside the fiber 10 . By providing the metal core 12 inside the fiber 10, the core 12 can be used to facilitate heating during manufacturing. Also, the metal core 12 can be used for heat dissipation when the obtained light-emitting device 100 is caused to emit light, which is expected to improve heat dissipation and stabilize the operation of the light-emitting device.

Tungsten or iridium can be suitably used as the metal forming such a core 12 . Tungsten is particularly preferable because of its excellent thermal conductivity. The thickness of the core 12 is set to 10 μmφ to 5 mmφ.

Further, it is preferable to connect the core body 12 to a heat radiation member. In the example of the light-emitting element 200 according to the modified example shown in FIG. 7, while the anode terminal and the cathode terminal are provided as the external connection terminals 30 around both ends of the filament-shaped light-emitting element 200, they are exposed at the center of the end face. The core 12 is thermally coupled with an external heat radiating member 40 . As a result, while supplying power from the end face of the fiber 10, it is possible to efficiently dissipate heat by providing a heat conduction path for conducting heat to the outside through a path other than the path for power supply. As the external heat radiation member 40, a heat exchanger such as a heat radiation fin, a heat radiation fan, a Peltier element, or a water cooling unit can be used.

Although the example of FIG. 7 shows an example in which the external connection terminals 30 are provided at both ends of the fiber 10, the present invention is not limited to this configuration, and the external connection terminals may be provided at arbitrary positions on the fiber. For example, an external connection terminal may be provided in the middle of the fiber.
(Semiconductor light emitting structure 20)

A semiconductor light emitting structure 20 is formed in the fiber 10A. As shown in the enlarged cross-sectional view of FIG. 3, the semiconductor light emitting structure 20 includes a light emitting layer 23, an n-type semiconductor layer 22 and a p-type semiconductor layer 24 with the light emitting layer 23 therebetween. An n-side electrode 27 and a p-side electrode 26 are electrically connected to the n-type semiconductor layer 22 and the p-type semiconductor layer 24, respectively. A low temperature growth buffer layer 21 is formed between the fiber substrate 10A and the n-type semiconductor layer 22, if necessary. Furthermore, a p-side contact layer 25 is formed between the p-type semiconductor layer 24 and the p-side electrode 26 .

The n-side electrode 27 and the p-side electrode 26 are electrically connected to the n-type semiconductor layer 22 and the p-type semiconductor layer 24, respectively. These electrodes are used as pad electrodes for soldering to the outside, and can be made of, for example, Au or an alloy containing Au as a main component.

The semiconductor light emitting structure 20 is preferably a nitride semiconductor laminated structure. By obtaining a semiconductor light-emitting device using a nitride-based semiconductor (InxAlyGa1 _-XYN , where _X and _Y satisfy 0≤X, 0≤Y, and X+Y≤1), Light with a wide range of wavelengths such as light, blue light, and green light can be obtained efficiently.

The plurality of semiconductor light emitting structures 20 are insulated with an insulating layer 28, as shown in the longitudinal cross-section of FIG. 2A. For such an insulating layer 28, a light-transmitting stable oxide such as SiO ₂ can be suitably used. The insulating layer 28 can also be used as a protective film that covers the surface of the semiconductor light emitting structure 20 to protect it from the outside. Alternatively, a protective film may be formed separately from the insulating layer 28, as shown in FIG. 2A and the like.
[Embodiment 5]

In the above example, multiple semiconductor light emitting structures are adjacent to each other along the length of the fiber. However, the present invention is not limited to this configuration, and may be a light-emitting element having one semiconductor light-emitting structure. Such an example is shown in FIGS. 8A and 8B as a light emitting device 500 according to the fifth embodiment. In this example, a semiconductor light emitting structure 20 is formed around a short cut fiber 10 . Each layer constituting the semiconductor light emitting structure 20 is the same as that of the first embodiment described above, and the same reference numerals are assigned to the layers, and detailed description thereof will be omitted. The light-emitting element 500 can be obtained by cutting the light-emitting element 100 shown in FIG. 2A into pieces by a predetermined length, for example.

Further, in order to supply power to the light emitting element 500 from the outside, it is preferable to form bumps 50 on each of the p-side electrode 26 and the n-side electrode 27 . A conductive member such as solder can be suitably used for the bump. Using this bump 50, it can also be used as a flip-chip type LED.
[Embodiment 6]

Furthermore, the light-emitting device according to Embodiment 6 is shown in the vertical cross-sectional view of FIG. 9A and the horizontal cross-sectional view of FIG. 9B. Each layer constituting the semiconductor light emitting structure 20 is the same as that of the above-described Embodiment 1, etc., and is denoted by the same reference numerals, and detailed description thereof will be omitted. A light-emitting device 600 shown in this figure is formed by insulating a plurality of semiconductor light-emitting structures 20 from each other with an insulating layer 28 in the extending direction of the fiber 10, as in the first embodiment. The p-side electrode 26 and the n-side electrode 27 of the semiconductor light emitting structure 20 separated on the outer periphery of the fiber 10 are metallized by vapor deposition, sputtering, or conductor printing so that they are connected in series between the adjacent semiconductor light emitting structures 20. A connecting layer 29 is connected. That is, the p-side electrode 26 and the n-side electrode 27 of the semiconductor light emitting structure 20 separated in a ring shape are electrically connected in series alternately with positive and negative. Thereby, a long LED in which a plurality of light emitting portions are connected in series can be configured. A pad electrode 52 is provided on the end surface of the LED as an overall electrode terminal. As shown in FIG. 9B, in this example, the cross-sectional shape of the fiber 10 is a vertically long elliptical shape, but it is not limited to this, and may be, for example, a horizontally long elliptical shape, a rectangular shape, or the like.
[Embodiment 7]

Furthermore, the light-emitting device according to Embodiment 7 is shown in the vertical cross-sectional view of FIG. 10A and the horizontal cross-sectional view of FIG. 10B. Each layer constituting the semiconductor light emitting structure 20 is the same as that of the above-described Embodiment 1, etc., and is denoted by the same reference numerals, and detailed description thereof will be omitted. A light-emitting device 700 shown in this figure has one semiconductor light-emitting structure 20 formed on the outer periphery of the fiber 10, as in the fifth embodiment. In addition, the p-type electrode is formed on the side near the n-side electrode 27, which provides advantages such as easy connection with an external electrode.
[Embodiment 8]

In the above example, the semiconductor light-emitting structure 20 is grown around the fiber 10 while the core 12 is held at the center of the fiber 10, and the core 12 is used for heat dissipation even after the light-emitting element is formed. explained. However, the present invention is not limited to this configuration, and may be configured such that after the growth of the semiconductor light emitting structure, the core is removed and another member is inserted. Such an example is shown in the longitudinal sectional view of FIG. 11A and the lateral sectional view of FIG. 11B as a light emitting device according to the eighth embodiment. Each layer constituting the semiconductor light emitting structure 20 is the same as that of the above-described Embodiment 1, etc., and is denoted by the same reference numerals, and detailed description thereof will be omitted. The light-emitting element 900 shown in this figure can also be used as an LED in which one semiconductor light-emitting structure 20 is formed on the outer periphery of the fiber 10, like the seventh embodiment. In this light-emitting device 900, the core is extracted after the growth of the semiconductor light-emitting structure 20, and the heat dissipation member 40B is inserted into the cavity as another core. The heat radiating member 40B is formed in a rod shape, and has a disk-shaped end face plate connected to its end. By inserting the heat dissipating member 40B having this structure as a new core material, a heat dissipating plate having a wider area can be exposed at the end surface of the light emitting element 900, so that the heat dissipating property can be further improved. Here, since it is assumed that the core is extracted, its material is not limited to tungsten, iridium, or the like. Moreover, it is preferable that the thickness of the core body is set to a certain size so that it can be extracted from the fiber 10 in advance and the heat radiating member 40B is inserted into the extracted cavity. For example, it is 25 μm to 50 mmφ.

In the example shown in FIG. 11A, an example is shown in which heat radiation members 40B having the same shape and having rod-like portions of about 1/2 the length of the fiber 10 are inserted from both sides of the fiber 10. However, this configuration is limited. Instead, for example, a heat dissipating member having a rod-like portion extended to a length substantially equal to the length of the fiber may be inserted from one end face of the fiber.
[Embodiment 9]

In the above examples such as Embodiment 1, the semiconductor light emitting structure 20 is divided along the extending direction of the fiber 10, and a plurality of semiconductor light emitting structures 20 are arranged in the extending direction. Not limited to configuration. For example, in a cross-sectional view of the fiber, the fiber may be divided in the circumferential direction to arrange the semiconductor light emitting structures. Such an example is shown in the longitudinal sectional view of FIG. 12A and the lateral sectional view of FIG. 12B as a light emitting device 1000 according to the ninth embodiment. Each layer constituting the semiconductor light emitting structure 20 is the same as that of the above-described Embodiment 1, etc., and is denoted by the same reference numerals, and detailed description thereof will be omitted. In the light emitting element 1000 shown in this figure, as shown in FIG. 12A, the semiconductor light emitting structure 20 is not divided in the extending direction of the fiber 10, and as shown in FIG. divides the semiconductor light emitting structure 20 at . The spaced apart semiconductor light emitting structures 20 are appropriately insulated with an insulating layer 28 or the like. The p-side electrodes 26 and the n-side electrodes 27 of the semiconductor light emitting structures 20 separated in the circumferential direction are connected in series between adjacent semiconductor light emitting structures 20 . Thereby, a long LED can be configured.

Furthermore, the separation of the semiconductor light-emitting structure can be divided both in the fiber extension direction and in the circumferential direction when viewed in cross section. In this case, the island-like semiconductor light-emitting structures can be arranged in a matrix while the fiber is unfolded.

As described above, the fiber 10 is a fibrous member for growing a semiconductor light emitting structure including a light emitting layer on its surface. This fiber 10 is composed of sapphire or spinel. Moreover, the metal core 12 is provided in the inside along the fibrous extension direction.

Also, it is preferable that <0001> of sapphire or <111> of spinel coincide with the cross-sectional direction intersecting the extending direction of the fiber 10 . Thereby, the semiconductor light emitting structure 20 can be efficiently grown on the side surface of the fiber 10 . In the example of FIG. 2A, the vertical direction of the fiber 10 is the c-axis of sapphire.

By arranging the semiconductor light emitting structure 20 around the fiber 10 in this way, it is possible to realize a string-like light emitting element. Conventionally, to obtain a string-shaped light-emitting element, it was necessary to stick individually produced LED chips linearly. That is, a laminated structure of nitride semiconductor or the like is formed on a planar growth substrate, cut into chips, and die-bonded to a mounting substrate of ceramic or the like. to obtain an LED chip. A large number of LED chips thus obtained are arranged in a line on an elongated ceramic substrate or the like. This method was inefficient in manufacturing and assembly, but as described above, according to the light-emitting device according to the present embodiment, by forming the semiconductor light-emitting structure 20 directly on the side surface of the fiber 10, a large number of light-emitting portions can be efficiently formed. It becomes possible to In addition, in the conventional configuration, it is difficult to efficiently dissipate the heat generated when a large number of LED chips are arranged to emit light. In particular, when a plurality of LED chips are arranged in an annular shape along the periphery of a cylinder, there is no path for discharging heat generated by heat conduction toward the center of the cylinder, and there is concern about deterioration due to heat. On the other hand, according to the light emitting device according to the present embodiment, by providing the metallic core body 12 in the fiber 10, the heat transferred toward the center of the fiber 10 can be effectively discharged to the outside. is possible, and heat dissipation is greatly improved. In addition, the core 12 can be used to heat the fiber substrate in the manufacturing process of the light emitting device. That is, by connecting the core body 12 to an external heat source such as a heater, the fiber 10 can be heated from the inside, which facilitates heating when the semiconductor light emitting structure 20 is grown around the fiber 10. It also has the advantage of being able to
[Fiber manufacturing method]

Here, a method for manufacturing the fiber will be described. This fiber 10 is a fibrous member for growing a semiconductor light emitting structure 20 on its surface.

First, a metal core 12 extended in a fibrous shape is prepared. Next, sapphire or spinel is grown around this core 12 .

In order to form the fiber 10 of sapphire, spinel, etc., it is preferable to use the growth method by the μ-PD method. This makes it possible to obtain a fiber that facilitates the growth of a semiconductor light-emitting structure, and facilitates the formation of the fiber at high speed. In addition, it can be grown with a free cross-sectional shape, can be produced in a near net shape, can be grown simultaneously with crystals, and can be grown at high speed with low raw material loss and low processing loss. Alternatively, the LHPD method can be used instead. As a result, it is possible to obtain a fiber that facilitates the growth of a semiconductor light emitting structure, and to reduce the amount of heat required to form the fiber. In other words, while the general fiber growing method requires melting all the raw materials, the LHPD method can melt only the necessary amount, and thus has the advantage of reducing the amount of heat to be applied. Moreover, the crucible can be dispensed with and the efficiency is excellent.
[Method for manufacturing light-emitting element]

Next, a method for manufacturing a light emitting device will be described with reference to FIGS. 13A to 16B. First, the fiber 10 is prepared. In this step, the fiber 10 including the metallic core body 12 made of sapphire or spinel is manufactured by using the above-described fiber manufacturing method or the like. This results in the fiber 10 shown in longitudinal section in FIG. 13A and transverse section in FIG. 13B.

Next, the semiconductor light emitting structure 20 is grown on the outer peripheral surface of the fiber 10 while the core 12 is heated. An example of this process is shown in FIG. Here, the produced fiber 10 is wound around a first drum, and the fiber 10 sent out from this first drum is wound by a second drum spaced apart from the first drum. During this time, heating is performed from the side to grow the semiconductor light emitting structure 20 . In this figure, the fiber 10 is delivered from left to right, and is divided into a plurality of steps. The steps are partitioned using an Ar curtain seal CS or the like.

First, in the first step at the left end, the fiber 10 is washed with HCl. Next, in the second step, the fiber 10 is made of single-crystal sapphire as a growth substrate, and a low temperature growth buffer layer 21 (for example, a GaN layer) is grown around this fiber substrate.

Next, as a third step, an n-type semiconductor layer 22 (here, an n-GaN layer) is grown on the upper surface of the low temperature growth buffer layer 21 . Next, as a fourth step, a light-emitting layer 23 (here, an InGaN layer) is grown on the upper surface of the n-type semiconductor layer 22 . Furthermore, as a fifth step, a p-type semiconductor layer 24 (here, a p-AlGaN layer) is grown on the upper surface of the light emitting layer 23 . Then, as a sixth step, the p-side contact layer 25 (here, p-GaN layer) is grown on the upper surface of the p-type semiconductor layer 24 . Also, in these steps, the heating is performed by irradiating, for example, a CO ₂ laser.

Thus, the fiber 10 on which the semiconductor light emitting device structure is grown is wound on a second drum. Further, if necessary, the semiconductor light emitting structure 20 is separated. Here, the etching separates the semiconductor light emitting structures 20 at regular intervals along the length of the fiber 10, as shown in the vertical cross-sectional view of FIG. 15A and the cross-sectional view of FIG. 15B. An insulating layer 28 is formed between the separated semiconductor light emitting structures 20 .

Further, metallization by vapor deposition, sputtering, or conductor printing is performed to electrically connect adjacent semiconductor light emitting structures 20 with a connection layer 29 . Here, as shown in the vertical cross-sectional view of FIG. 16A and the horizontal cross-sectional view of FIG. 16B, an n-side electrode 27 and a p-side electrode 26 are formed for each semiconductor light emitting structure 20 . After forming the protective film, a connection layer 29 for connecting the n-side electrode 27 and the adjacent p-side electrode 26 is formed and wired. Terminals for external connection are formed at the electrode portions located at the edges of the semiconductor light emitting structures 20 connected in series. In this way, a light-emitting device is obtained in which a plurality of semiconductor light-emitting structures 20 are connected in series.

INDUSTRIAL APPLICABILITY The light-emitting device and the manufacturing method thereof according to the present invention can be suitably used for filaments of incandescent LED lamps, string-like light sources arranged around the light guide plate of liquid crystal backlights, and the like.

DESCRIPTION OF SYMBOLS 100, 200, 500, 600, 700, 900, 1000... Light-emitting element 10, 10A, 10B, 10C, 10D... Fiber 12... Core body 20... Semiconductor light-emitting structure 21... Low temperature growth buffer layer 22... N-type semiconductor layer 23... Light-emitting layer 24 p-type semiconductor layer 25 p-side contact layer 26 p-side electrode 27 n-side electrode 28 insulating layer 29 connection layer 30 external connection terminals 40, 40B heat dissipation member 50 bump 52 bad electrode LB...light bulb CS...Ar curtain seal

Claims (12)

a fiber composed of sapphire or spinel;
a semiconductor light emitting structure formed on the outer peripheral surface of the fiber;
with
A light-emitting device in which the fiber has a metal core body extending along the extension direction of the fiber inside the fiber made of sapphire or spinel. The light emitting device according to claim 1,
The light-emitting device, wherein the core is tungsten or iridium. The light-emitting device according to claim 1 or 2,
The light emitting device, wherein the semiconductor light emitting structure is a nitride semiconductor laminated structure. The light emitting device according to any one of claims 1 to 3,
A light-emitting device in which <0001> of the sapphire or <111> of the spinel coincides with a cross-sectional direction intersecting the extending direction of the fiber. The light emitting device according to any one of claims 1 to 4,
A light-emitting device in which the fiber has a circular cross section. The light emitting device according to any one of claims 1 to 5,
A light-emitting device in which a plurality of the semiconductor light-emitting structures are spaced apart along the extension direction of the fiber. The light emitting device according to claim 6,
A light emitting device in which the separated semiconductor light emitting structures each have positive and negative electrode portions, and the respective semiconductor light emitting structures are connected in series via the respective electrode portions. The light emitting device according to any one of claims 1 to 7,
A light-emitting device in which the core body is connected to a heat dissipation member. A method for manufacturing a light emitting device,
Preparing a fiber made of sapphire or spinel and containing a filament-like elongated metal core inside;
growing a semiconductor light emitting structure on the outer peripheral surface of the fiber while the core is heated;
A method of manufacturing a light emitting device comprising: A method for manufacturing a light-emitting device according to claim 9,
<0001> of the sapphire or <111> of the spinel coincides with a cross-sectional direction that intersects the extending direction of the fiber. A method for manufacturing a light-emitting device according to claim 9 or 10,
A method of manufacturing a light-emitting device, wherein the step of preparing the fiber includes the step of growing the sapphire or spinel by a μ-PD method. A method for manufacturing a light-emitting device according to claim 9 or 10,
A method of manufacturing a light-emitting device, wherein the step of preparing the fiber includes the step of growing the sapphire or spinel by the LHPD method.

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